1. Field of the Invention
The present invention is related to the monitoring of erosion and corrosion in components of a containment system and, more particularly, to a system for monitoring wall thinning of pipes in a nuclear reactor due to corrosion and erosion.
2. Description of the Related Art
Any system of pipes, or more generally any containment system for containing flowing fluids, is subject to both corrosion and erosion which cause wall thinning. When the fluid is itself hazardous, e.g., toxic, radioactive, etc., or when loss of fluid is hazardous, e.g., in the cooling system of the nuclear reactor, maintaining containment integrity in the system is extremely important. Typically, such systems operate under pressure and if the wall thinning proceeds far enough, such walls can rupture causing loss of the fluid and resulting hazards.
As nuclear powered electricity generating plants have aged, wall thinning at plants has become an increasing concern of the Nuclear Regulatory Commission (NRC) which issued a bulletin on Jul. 9, 1987 requesting information regarding existing programs for avoiding detrimental effects from pipe wall thinning. NRC Informational Notice 88-17 dated Apr. 22, 1988 reported a summary of the response to the July 1987 request. According to this Notice, inspection programs existing at all plants surveyed indicate that corrosion or erosion exists at all plants and that feedwater condensate and recirculation systems are the most severely affected. According to the NRC April 1988 Notice, none of the plants responding to the July 1987 include systematic evaluations of the inspection data.